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Organophotoredox catalytic four-component radical-polar crossover cascade reactions for the stereoselective synthesis of β-amido sulfones with high atom-, step-, and redox economy and excellent diastereoselectivity.

A green and practical divergent Ritter-type amination via a photoredox catalytic four-component radical-polar crossover process was developed. This versatile protocol presents a modular and powerful strategy to access functionalized β-sulfonyl imides and imines under mild conditions from readily available and stable substrates with high atom-, step- and redox economy. We manipulated carboxylic acids and benzotriazoles to precisely attack the nitrilium ion instead of the carbocation, thus preventing many complicated side reactions of the photocatalytic reactions. Furthermore, the synthetic utility of this divergent Ritter reaction is further demonstrated by the late-stage modification of pharmaceutical and natural product derivatives.

Considering lifting scheme and traditional wavelet packet transform principle, The optimal lifting wavelet packet threshold denoising algorithm was introduced. Experimental blasting vibration signal was decomposed by optimal lifting wavelet packet, and noise components in blasting vibration measured signals were filtered successfully. Research shows that, lifting wavelet package transform can effectively remove noise components, and it laid an important foundation for lifting algorithm will be introduced into the analysis field of blasting vibration effects and other mechanical vibration signal.

A FeCl3-catalyzed highly regioselective 1,2-addition/substitution sequence of 3-acetylcoumarins and indoles has been developed to afford highly hindered tetrasubstituted bis(indolyl)methanes bearing a biologically useful coumarin motif in 56–99% yields.

A FeCl3-catalyzed highly regioselective 1,2-addition/substitution sequence of 3-acetylcoumarins and indoles has been developed to afford highly hindered tetrasubstituted bis(indolyl)methanes bearing a biologically useful coumarin motif in 56–99% yields.